Early and Late Outcomes of Surgery of Non-Complicated Liver Hydatid/Resultados Precoces y Tardios de la Cirugia de la Hidatidosis Hepatica no Complicada.
Hepatic echinococcosis (HE) is a common disease and a serious health problem in some geographical areas of Chile, one of which is La Araucania Region (Martinez, 2011), where approximately 60 new cases per year are surgically treated. The absence of standard surgical treatment represents a main problem (Dziri et al., 2004). It is clear however, that surgery remains the principal treatment for HE, should preserve liver function, have a low morbidity and mortality rate, and for it to be therapeutic, all living parasites must be removed and no viable daughter cysts (Fig. 1) or protoscolices left either in the residual cavity or anywhere else in the host.
However, despite this being a prevalent health problem, the information regarding HE surgery is not as extensively published as in other areas of surgery. Controversy persists regarding morbidity of HE surgery, because the behavior of this variable over time has not varied in a very relevant way, with heterogeneous reports independent of the place of production of the data. For example, in national articles of the 1990s, data of postoperative morbidity (POM) were reported from 49.0 % to 68.5 % (Sapunar et al., 1989; Hermosilla et al, 1991; Pinto, 1991; Apablaza et al, 1992; Camacho et al., 1996). Similar numbers were reported in foreign articles, with figures ranging from 34.7 % to 62.5 % (Gonzalez et al, 1999; Sarotto et al, 1999; Correa et al, 2000). After 2000, the reality did not improve substantially, as POM numbers were published from 21.3 % to 53.8 % (Yorganci et al, 2002; Nari et al., 2003; Atmatzidis et al., 2005; Daradkeh et al., 2007; Gourgiotis et al., 2007; Agayev & Agayev, 2008), a situation that could be explained by the heterogeneity of the populations analyzed in the different studies, which usually include patients with complicated and uncomplicated HE.
On the other hand, speaking POM is complex because of the multiplicity of variables that influence it, and because of the diversity in the severity of the complications and the implications of this variable in the prognosis of each patient.
Based on the above, Dindo & Clavien designed and validated a classification based on the severity of the POM, allowing having an instrument that homogenizes the POM data (Dindo et al., 2004; Clavien et al., 2009).
The aim of this study was to describe the early and late outcomes of a series of patients with uncomplicated liver hydatid cysts (NLHC) treated surgically.
This manuscript was written according to the guidelines of the MInCir initiative for the reporting of outcomes of descriptive observational studies (Manterola & Otzen, 2017a).
MATERIAL AND METHOD
Design: Concurrent cohort study, without comparison group.
Setting: The study was conducted in the Surgical Services of the Hospital Regional and the Clinica Mayor in Temuco, Chile between January 2000 and December 2015 (16 years).
Participants: Patients operated on for NLHC by the first author (CM), in the centers aforementioned during the study period were included. Patients treated laparoscopically, with concomitant hydatidosis in another location, previously operated for liver hydatidosis, and with some evolutionary complications of the disease (Manterola & Urrutia, 2015a): liver abscess of hydatid origin (Manterola et al., 2003a; ; Manterola et al., 2009a; Manterola & Urrutia, 2015b), cholangiohidatidosis (Manterola et al., 2001; Manterola & Otzen, 2017b), thoracic involvement (Manterola et al., 2009b; Manterola & Otzen, 2017c), hydatid peritonitis (Manterola et al., 2003b), anaphylaxis, and fistulization of the cyst to some structure of the digestive tract were excluded.
Study protocol: All patients were studied with general laboratory tests, immunodiagnostic and imaging (ultrasonography or CT scan (Fig. 2)).
Sampling: Non-probabilistic sample of consecutive cases.
Variables: Outcome variables were: "development of POM", dichotomously (yes/no, early/late and medical or surgical treatment), and applying the Dindo & Clavien proposal (Table I) (Dindo et al.; Clavien et al.), measured at least 12 months after surgery. Hospital stay, need for reoperation, mortality and recurrence.
Follow-up: After hospital discharge patients were followed up at months 1, 6, 12, 24, 36, 48, 60 and thereafter once a year with clinical monitoring, lab tests, immunodiagnostics with ELISA-IgG y ELISA-IgE (Manterola et al., 2007), abdominal ultrasonography and thorax x-ray.
Biases: At the time of the recruitment as well as at the time of clinical check-ups, biases were reduced with a complete follow-up of the patients comprising this series. Furthermore, data collection was masked.
Study size: Since it is an observational and descriptive study, no sample size was estimated.
Treatment: All patients underwent emergency surgery with prior antibiotic prophylaxis. There was no standard treatment, since the surgical procedures used were applied according to the intraoperative findings. According to these, total or subtotal percystectomy (Figs. 3 and 4) and hepatic resection were performed.
1. NLHC was defined as exclusive hepatic hydatid disease without evolutionary complications. Independent of the number of cysts, the diameter of the main lesion, the existence of biliary communications and cyst relationship with perihepatic vascular structures (Figs. 3 and 4).
2. Recurrence was defined as the appearance of abdominal hydatidosis at any location, after one year of surgery.
Statistics: An exploratory data analysis was performed. Subsequently, descriptive statistics were used to calculate percentages, averages and standard deviations, medians and extreme values. Finally, incidence or absolute risk for the development of POM, reoperation, and recurrence was calculated.
Ethical principles: Written informed consent was obtained from each patient. All the ethical guidelines for research on human beings as defined by the Helsinki Declaration (Helsinki Statement of the World Wide Medical Association, 2000) were observed.
Funding: This study was partially financed by project DIDUFRO DI16-0119.
A total of 136 patients operated on for NLHC were recruited in this period, with no loss of follow-up (Fig. 5). Thirty-eight patients (27.9 %) had comorbidities among which stand out the cholelithiasis (21 cases, 15.4 %) (Table II).
The patients comprising the cohort are characterized by a median age of 41 years (15 a 84 anos), 60.3 % female and 30.9 % of them having two or more cysts with a mean diameter of 14.9+5.9 cm (Table III).
Laboratory tests revealed median normal values (Table III), and regarding the qualitative measurements of specific immunoglobulin, IgG-ELISA and ELISA-IgE was positive in 69.9 % and 55.1 % of cases respectively.
The 136 subjects in the study had a total of 204 cysts of different size and location. Cysts were preferentially located in the right lobe (63.2 %) and were hypoechoic in 61.0 % of the cases (Table IV).
The median surgical time was 95 min. And the most frequently used surgical procedure was total or subtotal pericystectomy (86.8 %). Eighty-one of major cysts (59.6 %), had biliary communications (25.0 % had two or more). On the other hand, in 75.0 % of the cases, another surgical procedure was performed concomitantly (Table IV).
The incidence or absolute risk of POM was 9.6 % (13 patients throughout the follow-up period). Eleven patients (8.1 %), developed early POM and two (1.5 %), late complications. When applying the classification of Dindo & Clavien, it was verified that in 92.3 % of the patients in whom MPO was registered, this was Grade I or II. The etiology was ungrouped as follows: 8 cases (5.9 %), of complications of medical treatment (5 cases of atelectasis, 2 of acute postoperative bronchitis and one case of urinary tract infection); and 5 cases (3.7 %), of complications of surgical treatment (3 cases of infection of the superficial operative site, 1 case of residual cavity and 1 case of eventration [the latter two required a surgical reoperation, representing an incidence of reoperation of 1.47 % in the follow-up period]) (Table V).
The median of hospital stay was 4 days (2 a 27 days).
No mortality was registered in the cohort.
With a median follow-up of 115 months respectively (12 to 190 months), one case of recurrence was verified, which represented an incidence of 0.7 % for the period. This case was diagnosed three years after the primary surgery, and was operated 5 months after the diagnosis was made.
There are a small amount of reports regarding the study of early and late outcomes of surgery for NLHC, and most are retrospective case series, contributing evidence level 4. This is how when performing a bibliographic search in PubMed database using the search strategy "Echinococcosis, Hepatic/surgery"[Mesh] OR "Liver hydatid cyst", a total of2263 records were obtained which when debugged through the application of the Boolean operator NOT ("alveolar echinococcosis", "pulmonary echinococcosis", "lung echinococcosis", spleen, complicated, "pharmacological treatment", "laparoscopic surgery", PAIR, percutaneous, endoscopic), and some limits (articles published since 2005 to the date of the review [03/31/2017], in human and adult population), generated an amount of 217 articles. However, when we added limits related to the type of design of the articles seeking the best level of evidence (systematic reviews with or without meta-analysis, clinical trials with random assignment), the search generated only a total of 6 articles. This means that, in the period of this search, more than 95 % of the articles referring to HE surgery are series of cases, most of which contain heterogeneous populations and, therefore with results whose internal validity is objectionable.
Notwithstanding all of the above, it is outstanding that in spite of the technological advance, POM of HE persists high (rates from 21.3 % to 53.8 %) (Yorganci et al.; Nari et al.; Atmatzidis et al.; Daradkeh et al.; Gourgiotis et al., 2007; Agayev & Agayev), especially because is considered to be a benign disease.
We believe that the reported POM (9.6 %) is relevant, however certain clinical characteristics of these patients, such as their concomitant comorbidities (in 16.2 % of patients triggered the need for concomitant surgeries), number and diameter of cysts, presence of biliary communication (59.6 % of cases), etc. variables associated with increased POM (Manterola et al., 2005; Manterola et al., 2010; Bedioui et al., 2012; Manterola et al., 2014; Baraket et al., 2014). This POM rate is among previously published ranks (10.8 % to 24.3 %) (Ozacmak et al., 2000; Atmatzidis et al.; Reza Mousavi et al., 2005; Gourgiotis, 2007; Agayev & Agayev; Yuksel, 2008; Manterola et al., 2013; Mosaddeghi et al., 2014; Manterola et al., 2014), to which must be added that the severity of complications is mostly low, and only 38.5 % of the cases were of surgical treatment with a lower incidence of re-interventions than reported (Bektas et al., 2001). On the other hand, the reported morbidity was analyzed over an extended follow-up period (115 months), which far exceeds previous reports.
The median length of hospital stay of 4 days is less than previously published data ranging from 6.5 to 23 days (Franciosi et al., 2002; Nari et al.; Hofstetter et al., 2004; Atmatzidis et al.; Reza Mousavi et al.; Prousalidis et al., 2009).
Moreover, the incidence of recurrence (0.7 % in the study period), also contrasts with previous numbers ranging between 1.5 % and 7.3 % (Nari et al.; Hofstetter et al.; Kapan et al., 2006; Gourgiotis et al., 2007; Prousalidis et al.), to which the long follow-up period has been added.
Finally, the absence of mortality of this cohort stands out when comparing it with different series, in which rates between 0.3 % and 3.7 % have been reported (Franciosi et al., 2002; Nari et al.; Cooney et al., 2004; Atmatzidis et al.; Kapan et al.; Gourgiotis et al., 2007; Daradkeh et al.; Agayev & Agayev; Prousalidis).
The novelty of this proposal is related to: the design used, which despite being a heterogeneous population, are patients with uncomplicated hepatic hydatidosis and with an extensive follow-up period (minimum 12 months). This makes it possible to verify the late POM that is not usually reported in most publications.
However, we are aware that the study presents some potential sources of bias that merit comment. One of these has to do with the heterogeneity of the population. Another is related to the sample size, because there are no more cases to report. However, complete follow-up of the cohort and extended follow-up time are tools that enhance data quality.
By way of conclusion, we can note that POM was determined in a cohort of patients with NLHC throughout an extended follow-up period, and the incidence and gravity of POM is smaller and of lower gravity than those previously published.
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Dr. Carlos Manterola
Department of Surgery and CEMyQ
Universidad de La Frontera.
Manuel Montt 112, office 408
Carlos Manterola (1); Tamara Otzen (2) & MINCIR group.
(1) Department of Surgery and Center of Excellence in Morphological and Surgical Studies (CEMyQ), Universidad de La Frontera, Temuco, Chile.
(2) Universidad de Tarapaca, Arica, Chile.
Partially financed by project DID-UFRO DI16-0119.
Caption: Fig. 1. Piece of germinal layer and daughter vesicles obtained from an NLHC.
Caption: Fig. 2. CT Scan in which a NLHC compromises segments V and VI is observed.
Caption: Fig. 3. NLHC 20 cm larger diameter, which compromises VI and VII segments. A subtotal pericystectomy is being performed, appreciating the entire pericystic layer.
Caption: Fig. 4. NLHC 25 cm larger diameter, which compromises IVb, V and III segments. A subtotal pericystectomy was performed, leaving a pericyst plaque in the center of the bloody area.
Caption: Fig. 5. Flow-chart of participants.
Table I. Dindo & Clavien Proposal. Grade Definition and examples Any deviation from normal postoperative course not requiring pharmacological, endoscopic, surgical or I interventional radiology treatment. It allows application of pharmacological treatments such as antiemetic's agents. antipyretics, analgesics, electrolyte solutions and physiotherapy. Includes infection of surgical wound treatable in the patient's bed. Example: Atrial fibrillation converted after correction of potassium levels. Pulmonary atelectasis requiring physical therapy. Non-infectious diarrhea. Surgical wound superficial infection. II It requires drug treatment with drugs other than the above. Includes transfusion of blood products and total parenteral nutrition. Example: Tachyarrhythmia requiring pharmacological treatment. Pneumonia treated with antibiotics. Diarrhea requiring antibiotics. Urinary tract infection requiring antibiotics. III It requires surgical, endoscopic or radiological intervention. a Without general anesthesia. Example: Bradyarrhythmia requiring pacemaker under local anesthesia. Bilioma requiring percutaneous drainage. Closure of uninfected dehiscent wound with local anesthesia. With general anesthesia. Example: Cardiac tamponade b requiring pericardial window. Bronchopleural fistula requiring surgical closure. Anastomotic fistula requiring relaparotomy. Infection of the surgical wound leading to eventration. IV Life-threatening complications that require treatment in units of intermediate or intensive care. Single organic dysfunction. a Example: Heart failure leading to low output syndrome. Respiratory failure requiring intubation. Stroke. Necrotizing pancreatitis. Acute renal failure requiring dialysis. Multiple organic dysfunctions. b Example: Heart failure leading to low output syndrome in combination with renal failure. Respiratory failure requiring intubation associated with renal failure. Stroke with respiratory failure. V Death of the patient. Suffix "d" If patient suffers complications at discharge, to the respective degree is added the suffix "d" (disability). Indicates the need for follow-up for a correct evaluation of the complication. Note: Adaptation of original text. Table II. Concomitant comorbidity of the patients in study (N = 136). Variable No cases % Concomitant pathology (%) No diseases 98 72.1 Cholelithiasis 21 15.4 Chronic airflow limitation 5 3.7 Heart failure 5 3.7 Hepatic cirrhosis 3 2.3 Heart failure + Diabetes mellitus 1 0.7 Chronic renal failure 1 0.7 Pregnancy (*) 1 0.7 Abdominal trauma (**) 1 0.7 (*): 15 weeks pregnancy (**): Hepatic hydatidosis was an intraoperative finding during exploratory laparotomy due to abdominal trauma and was treated at the same surgical time. Table III. Distribution of continuous variables of patients in study (N = 136). Variable Median Extreme values Age (years) 41.0 15-84 Hematocrit (%) 39.0 30-54 Leukocytes (x [mm.sup.3]) 7650.0 3400-15400 Total bilirubin (mg%) 0.6 0,1-2,7 Alkaline phosphatases (U/l) 291.5 60-3450 Aspartate aminotransferase (U/l) 24.0 10-407 Alanine aminotransferase (U/l) 24.5 8-436 Cyst diameter (cm.) 15.0 30-Jul Hospital stay (days) 4.0 27-Feb Follow-up (months) 115.0 12-190 Variable Average [+ or -] SD Age (years) 43.3 [+ or -] 17,2 Hematocrit (%) 39.1 [+ or -] 4.0 Leukocytes (x [mm.sup.3]) 7919.4 [+ or -] 2583.7 Total bilirubin (mg%) 0.8 [+ or -] 0.1 Alkaline phosphatases (U/l) 418.1 [+ or -] 408.1 Aspartate aminotransferase (U/l) 38.0 [+ or -] 45.8 Alanine aminotransferase (U/l) 40.0 [+ or -] 56.3 Cyst diameter (cm.) 14.9 [+ or -] 5.9 Hospital stay (days) 5.1 [+ or -] 2.9 Follow-up (months) 102.6 [+ or -] 45.2 SD: Standard deviation Table IV. Distribution of Categorical Variables of Patients in Study (N = 136) Variable No casEs % Ultrasonographic Characteristics of Cysts (*) Hypoechoic 83 61.1 Heterogeneous 49 36.0 Hyperechoic 4 2.9 Location of the cyst (*) Right lobe 86 63.2 Left lobe 28 20.6 Bilateral 22 16.2 Number of cysts One 94 69.1 Two 31 22.8 Three or more 11 8.1 Biliary communications (*) None 55 40.4 One 47 34.6 Two or more 34 25.0 Surgery performed (*) Total or partial pericystectomy 118 86.8 Liver resection 18 13.2 Additional Surgical Procedures None 34 25.0 Cholecystectomy 80 58.8 Cholecystectomy and choledochostomy 20 14.7 Choledochostomy 2 1.5 (*): It refers to the main lesion in those patients who had two or more cysts Table V. Morbidity of study patients (N = 136). Variable No cases % Dindo & Clavien Grade 0 123 90.4 Grade I 9 6.7 Grade II 3 2.2 Grade III 0 0.0 Grade IV 1 0.7 Grade V 0 0.0 Morbidity None 123 90.4 Respiratory 7 5.3 Surgical site infection 3 2.2 Urinary tract infection 1 0.7 Residual cavity 1 0.7 Incisional hernia 1 0.7